Resistive switching random access memory based on Sn-incorporated Cs(Pb_xSn_1-x)Br₃ perovskite thin films

We investigated the performance of resistive random access memory (RRAM) consisting of Sn-incorporated Cs(Pb_xSn_1-x)Br₃ thin films. The uniform Cs(Pb_xSn_1-x)Br₃ perovskite thin films with various Sn contents were formed by using the solution-based spin coating method. The structural and optical investigations showed that the Sn element was successfully incorporated into the CsPbBr₃ lattice. As the Sn content increases, secondary phases like SnBr₂ and CsSn₂Br₅ were al so formed in the Cs(Pb_xSn_1-x)Br₃ perovskite thin films. RRAM device consisting of the pristine CsPbBr₃ thin film showed typical RRAM switching behavior and an operating voltage of about 0.7 V. The RRAM switching behavior of the CsPbBr₃ was suggested based on the migration of halide vacancies, which forms the conducting filament when the electric field is applied. As the content of the Sn element increases, the transition voltage shifted to the lower voltage side to about 0.3~0.4 V. The switching performances of the RRAM device were affected by the Sn content in the Cs(Pb_xSn_1-x)Br₃ perovskite thin films due to the formation of defects and secondary phases.